热处理对铜锌合金微观组织和阻垢性能的影响

Effect of heat treatment on microstructure and incrustation inhibition properties of copper⁃zinc alloys

为了解决水垢对锅炉、管道等工业设备的损害问题,设计熔炼出一种新型的阻垢合金。通过扫描电镜、EDS能谱仪、X射线衍射仪、电化学工作站和接触角测量仪等设备对铜锌合金热处理前后的微观结构和表面性能进行表征。通过自主搭建的水循环平台进行试验,测定了水循环试验后溶液中剩余Ca2+浓度和铜锌合金阻垢率变化。收集循环水中的水垢,分析其微观形貌和晶体结构变化。结果表明,600℃热处理后铜锌合金的耐蚀性最好,自腐蚀电流密度为4.27μA·cm^(-2),并且具有最好的阻垢性能,试验溶液被600℃热处理的合金处理后静置0.5 h时,阻垢率可以达到90.27%,相较于铸态合金阻垢率(79.21%)提高了11.06%。该铜锌阻垢合金处理液具有一定时效性,在2 h内阻垢效果最佳。600℃热处理的铜锌合金使块状方解石转变为针状文石的能力更强,用其处理溶液后生成的水垢中方解石与文石比例为1.38∶1。

In order to solve the problem of incrustation damage to boilers,pipelines and other industrial equipment,a new type of incrustation inhibition alloy was designed and melted.The microstructure and surface properties of the copper⁃zinc alloy before and after heat treatment were characterized by means of scanning electron microscope,EDS energy spectrometer,X⁃ray diffractometer,electrochemical workstation and contact angle measuring instrument.The test was conducted on the independently built water circulation platform,and the residual Ca 2+concentration in the solution and the change of incrustation inhibition rate of the Cu⁃Zn alloy were determined after the water circulation experiment.The incrustation in the circulating water was collected and analyzed for micro⁃morphology and crystal structure changes.The results show that the copper⁃zinc alloy has the best corrosion resistance after heat treatment at 600℃,with a self⁃corrosion current density of 4.27μA·cm^(-2),and has the best incrustation inhibition properties,and the incrustation inhibition rate of the test solution can reach 90.27%when it is left to stand for 0.5 h after being treated with the alloy heat⁃treated at 600℃,which is an improvement of 11.06%in comparison with that of the as⁃cast alloy,the as⁃cast alloy has a incrustation inhibition rate of 79.21%.The copper⁃zinc incrustation inhibition alloy treatment solution has a certain timeliness,incrustation inhibition effect in 2 h is the best.The copper⁃zinc alloy after heat⁃treatment at 600℃has a stronger ability to transform the block calcite into needle aragonite,the ratio of calcite to aragonite after the generation of incrustation by treating the solution with which is 1.38∶1.